malabsorption

Your small intestine does most of the digesting of the foods you eat. If you have a malabsorption syndrome, your small intestine cannot absorb nutrients from foods.

Causes of malabsorption syndromes include:

• Celiac disease
• Lactose intolerance
• Short bowel syndrome. This happens after surgery to remove half or more of the small intestine. You might need the surgery if you have a problem with the small intestine from a disease, injury, or birth defect.
• Whipple disease, a rare bacterial infection
• Genetic diseases
• Certain medicines

Symptoms of different malabsorption syndromes can vary. They often include chronic diarrhea, abnormal stools, weight loss, and gas. Your doctor may use lab, imaging, or other tests to make a diagnosis.

Treatment of malabsorption syndromes depends on the cause.

If you have anemia, your blood does not carry enough oxygen to the rest of your body. The most common cause of anemia is not having enough iron. Your body needs iron to make hemoglobin. Hemoglobin is an iron-rich protein that gives the red color to blood. It carries oxygen from the lungs to the rest of the body.

Anemia has three main causes: blood loss, lack of red blood cell production, and high rates of red blood cell destruction.

Conditions that may lead to anemia include:

• Heavy periods
• Pregnancy
• Ulcers
• Colon polyps or colon cancer
• Inherited disorders
• A diet that does not have enough iron, folic acid or vitamin B12
• Blood disorders such as sickle cell anemia and thalassemia, or cancer
• Aplastic anemia, a condition that can be inherited or acquired
• G6PD deficiency, a metabolic disorder

Anemia can make you feel tired, cold, dizzy, and irritable. You may be short of breath or have a headache.

Your doctor will diagnose anemia with a physical exam and blood tests. Treatment depends on the kind of anemia you have.

NIH: National Heart, Lung, and Blood Institute

When you eat, your body breaks food down to a form it can use to build and nourish cells and provide energy. This process is called digestion.

Your digestive system is a series of hollow organs joined in a long, twisting tube. It runs from your mouth to your anus and includes your esophagus, stomach, and small and large intestines. Your liver, gallbladder and pancreas are also involved. They produce juices to help digestion.

There are many types of digestive disorders. The symptoms vary widely depending on the problem. In general, you should see your doctor if you have:

• Blood in your stool
• Changes in bowel habits
• Severe abdominal pain
• Unintentional weight loss
• Heartburn not relieved by antacids

NIH: National Institute of Diabetes and Digestive and Kidney Diseases

Folic acid is a B vitamin. It helps the body make healthy new cells. Everyone needs folic acid. For women who may get pregnant, it is really important. Getting enough folic acid before and during pregnancy can prevent major birth defects of her baby's brain or spine.

Foods with folic acid in them include:

• Leafy green vegetables
• Fruits
• Dried beans, peas, and nuts
• Enriched breads, cereals and other grain products

If you don't get enough folic acid from the foods you eat, you can also take it as a dietary supplement.

NIH: National Institutes of Health Office of Dietary Supplements

Food provides the energy and nutrients you need to be healthy. If you don't get enough nutrients -- including proteins, carbohydrates, fats, vitamins, and minerals - you may suffer from malnutrition.

Causes of malnutrition include:

• Lack of specific nutrients in your diet. Even the lack of one vitamin can lead to malnutrition.
• An unbalanced diet
• Certain medical problems, such as malabsorption syndromes and cancers

Symptoms may include fatigue, dizziness, and weight loss. Or, you may have no symptoms. To diagnose the cause of the problem, your doctor may do blood tests and a nutritional assessment. Treatment may include replacing the missing nutrients and treating the underlying cause.

Vitamin D deficiency means that your body is not getting enough vitamin D to stay healthy.

Vitamin D helps your body absorb calcium. Calcium is one of the main building blocks of bone. Vitamin D also has a role in your nervous, muscle, and immune systems.

You can get vitamin D in three ways: through your skin, from your diet, and from supplements. Your body forms vitamin D naturally after exposure to sunlight. But too much sun exposure can lead to skin aging and skin cancer, so many people try to get their vitamin D from other sources.

The amount of vitamin D you need each day depends on your age. The recommended amounts, in international units (IU), are:

• Birth to 12 months: 400 IU
• Children 1-13 years: 600 IU
• Teens 14-18 years: 600 IU
• Adults 19-70 years: 600 IU
• Adults 71 years and older: 800 IU
• Pregnant and breastfeeding women: 600 IU

People at high risk of vitamin D deficiency may need more. Check with your health care provider about how much you need.

You can become deficient in vitamin D for different reasons:

• You don't get enough vitamin D in your diet
• You don't absorb enough vitamin D from food (a malabsorption problem)
• You don't get enough exposure to sunlight
• Your liver or kidneys cannot convert vitamin D to its active form in the body
• You take medicines that interfere with your body's ability to convert or absorb vitamin D

Some people are at higher risk of vitamin D deficiency:

• Breastfed infants, because human milk is a poor source of vitamin D. If you are breastfeeding, give your infant a supplement of 400 IU of vitamin D every day.
• Older adults, because your skin doesn't make vitamin D when exposed to sunlight as efficiently as when you were young, and your kidneys are less able to convert vitamin D to its active form.
• People with dark skin, which has less ability to produce vitamin D from the sun.
• People with conditions that make it difficult to absorb nutrients from food, such as Crohn's disease, ulcerative colitis, and celiac disease.
• People who have obesity, because their body fat binds to some vitamin D and prevents it from getting into the blood.
• People who have had gastric bypass surgery, a type of weight loss surgery which creates a bypass of part of the small intestine. Since vitamin D is absorbed there, bypassing part of it makes it harder to absorb enough vitamin D.
• People with chronic kidney or liver disease, which can affect your ability to change vitamin D into a form your body can use.
• People who take medicines that affect vitamin D levels, including certain cholesterol, anti-seizure, steroid, and weight-loss medicines.

Talk with your provider if you are at risk for vitamin D deficiency. There is a blood test that can measure how much vitamin D is in your body.

Vitamin D deficiency can lead to a loss of bone density, which can contribute to osteoporosis and fractures (broken bones).

Severe vitamin D deficiency can also lead to other diseases:

• In children, it can cause rickets. Rickets is a rare disease that causes the bones to become soft and bend. African American infants and children are at higher risk of getting rickets.
• In adults, severe vitamin D deficiency leads to osteomalacia. Osteomalacia causes weak bones, bone pain, and muscle weakness.

There are a few foods that naturally have some vitamin D:

• Fatty fish such as salmon, tuna, and mackerel
• Beef liver
• Cheese
• Mushrooms
• Egg yolks

You can also get vitamin D from fortified foods. You can check the food labels to find out whether a food has vitamin D. Foods that often have added vitamin D include:

• Milk
• Breakfast cereals
• Orange juice
• Other dairy products, such as yogurt
• Soy drinks

Vitamin D is in many multivitamins. There are also vitamin D supplements, both in pills and in a liquid for babies.

If you have vitamin D deficiency, the treatment is with supplements. Check with your provider about how much you need to take, how often you need to take it, and how long you need to take it.

Getting too much vitamin D (known as vitamin D toxicity) can be harmful. Signs of toxicity include nausea and vomiting, poor appetite, constipation, weakness, and weight loss.

Very high levels of vitamin D can damage the kidneys. It also raises the level of calcium in your blood. High levels of blood calcium (hypercalcemia) can cause confusion, kidney failure, and irregular heartbeat (arrhythmia).

Most cases of vitamin D toxicity happen when someone overuses vitamin D supplements. You cannot get too much vitamin D from sun exposure because the skin limits the amount of vitamin D it makes.

Metabolism is the process your body uses to get or make energy from the food you eat. Food is made up of proteins, carbohydrates, and fats. Chemicals in your digestive system break the food parts down into sugars and acids, your body's fuel. Your body can use this fuel right away, or it can store the energy in your body tissues, such as your liver, muscles, and body fat.

A metabolic disorder occurs when abnormal chemical reactions in your body disrupt this process. When this happens, you might have too much of some substances or too little of other ones that you need to stay healthy. There are different groups of disorders. Some affect the breakdown of amino acids, carbohydrates, or lipids. Another group, mitochondrial diseases, affects the parts of the cells that produce the energy.

You can develop a metabolic disorder when some organs, such as your liver or pancreas, become diseased or do not function normally. Diabetes is an example.

Your small intestine is the longest part of your digestive system - about twenty feet long! It connects your stomach to your large intestine (or colon) and folds many times to fit inside your abdomen. Your small intestine does most of the digesting of the foods you eat. It has three areas called the duodenum, the ileum, and the jejunum.

Problems with the small intestine can include:

• Bleeding
• Celiac disease
• Crohn's disease
• Infections
• Intestinal cancer
• Intestinal obstruction
• Irritable bowel syndrome
• Ulcers, such as peptic ulcer

Treatment of disorders of the small intestine depends on the cause.